CXCL16 and glioblastoma: Moreover, C-X-C motif chemokine ligand (CXCL) 16 (CXCL16) is secreted by glioblastoma cells, and by signaling through C-X-C motif chemokine receptor (CXCR) 6 (CXCR6) it polarizes TAMs towards the M2-like phenotype.